89711821 has 2 divisors, whose sum is σ = 89711822. Its totient is φ = 89711820.

The previous prime is 89711807. The next prime is 89711827. The reversal of 89711821 is 12811798.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 88566921 + 1144900 = 9411^2 + 1070^2 .

It is a cyclic number.

It is not a de Polignac number, because 89711821 - 2⁷ = 89711693 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (89711827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 44855910 + 44855911.

It is an arithmetic number, because the mean of its divisors is an integer number (44855911).

Almost surely, 2^89711821 is an apocalyptic number.

It is an amenable number.

89711821 is a deficient number, since it is larger than the sum of its proper divisors (1).

89711821 is an equidigital number, since it uses as much as digits as its factorization.

89711821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8064, while the sum is 37.

The square root of 89711821 is about 9471.6324358581. The cubic root of 89711821 is about 447.6616496205.

The spelling of 89711821 in words is "eighty-nine million, seven hundred eleven thousand, eight hundred twenty-one".